title: Photosensitizing properties of water-extractable organic matter from soils.
abstract: Water-extractable organic matter (WEOM) was extracted using pure water from two black soils and from the Elliott reference soil of the International Humic Substances Society (IHSS). WEOMs were characterized by chemical and spectroscopic methods. The apparent quantum yields of singlet oxygen, triplet excited states and hydroxyl radicals formation upon irradiation within the wavelength range 290-450 nm were determined using chemical probes and compared to those of standard Elliott humic substances. In general, the aromatic content, as measured by the SUVA value, was close in WEOMs and humic substances, while the E2/E3 was higher and the humification index lower in the former. Quantum yield values measured for WEOMs fell within the range of those found for basic medium extracted humic substances or were even higher in one case. Thus, water soluble aromatic moiety of the soil organic matter, especially those with low humification degree, is important for the photosensitizing properties. We also found that WEOMs sensitized the bisphenol A phototransformation with rates of the same order of magnitude for all the samples.
authors.affiliation: Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France.
authors.forename: Ezzhora
authors.initials: E
authors.lastname: Nkhili
authors.forename: Patrycja
authors.initials: P
authors.lastname: Boguta
authors.forename: Romualda
authors.initials: R
authors.lastname: Bejger
authors.forename: Ghislain
authors.initials: G
authors.lastname: Guyot
authors.forename: Zofia
authors.initials: Z
authors.lastname: Sokołowska
authors.forename: Claire
authors.initials: C
authors.lastname: Richard
mesh_terms: D006812:Humic Substances / Q000032:analysis*; D055668:Photochemical Processes; D026082:Singlet Oxygen; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D013057:Spectrum Analysis
chemical_list: D006812:Humic Substances; D012987:Soil; D012989:Soil Pollutants; D026082:Singlet Oxygen
keywords: Bisphenol A; Hydroxyl radicals; Sensitizing properties; Singlet oxygen; Triplet excited states; Water-soluble soil organic matter